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Foliar Corn Diseases In South Dakota: Visual Disease Surveys And The Genetic Studies Of Tar Spot And Bacterial Leaf Streak, Ciera Kotaska

Electronic Theses and Dissertations

Corn (Zea mays L.) is one of the most important crops in South Dakota and the United States. Each year, a variety of diseases impact the production of corn in South Dakota, though very little documentation about these diseases exists in the state. This survey documents the foliar diseases of corn and the distribution of each to create a baseline of knowledge. An additional genetic study was conducted to determine the organisms associated with tar spot of corn and bacterial leaf streak (BLS), two emerging diseases in South Dakota. A variety of studies have been conducted on tar spot, caused …

Evaluation Of Strip-Tillage And Banded Phosphorus And Potassium Fertilizer For Corn Production In Eastern South Dakota, Charles N. Tesch

Electronic Theses and Dissertations

In South Dakota, the adoption of no-till and other conservation tillage practices has grown in recent years. However, conventional tillage is still a common practice in the eastern third of the state, negatively affecting soil health and the environment. Strip-tillage has gained interest in this region as a way to transition to conservation tillage while retaining some benefits of conventional tillage. Strip-tillage also provides the ability to subsurface band nutrients, particularly phosphorus (P) and potassium (K) fertilizers within the tillage strip, potentially improving nutrient accessibility and recovery while reducing environmental risks. This study aimed to investigate (i) the effects of …

Quantification Of Auxin-Cytokinin Response During Lateral Root And Nodule Development In Medicago, Aniket Singh

Electronic Theses and Dissertations

Lateral roots (LRs) and nodules are post-embryonic root organs in legumes formed through the activity of de novo meristem. LRs, which are present in all vascular plants, are developed primarily via intrinsic developmental cues, whereas root nodules, found only in a small group of plants known as legumes, are formed in response to legume–rhizobium symbiosis. LRs arise from the pericycle layer of the root, whereas nodule initiation can begin either in the pericycle (indeterminate nodules with persistent meristem, as in Medicago) or in the cortex (determinate nodules with transient meristem, as in soybean), pointing toward a conserved developmental origin, especially …

Fungal Biotransformation Of Thin Stillage And Soybean Hulls And Bacterial Production Of Lysine In Ethanol Industry Co-Products, Bhawana Khadka

Electronic Theses and Dissertations

Thin stillage (TS) and whole stillage (WS) are major by-products of the corn ethanol industry. These by-products are generated in large quantities and contain nutrients that remain after yeast fermentation. Current industrial utilization of these by-products involves a series of downstream processing steps such as centrifugation and evaporation, which are energy-intensive and often result in nutrient losses. Traditionally, these by-products are dried to produce distillers dried grains with solubles. In this study, microbial fermentation was investigated as an alternative bioprocessing tool to expand the utilization of these by-products. The first objective was to explore the upcycling of TS, both alone …

Performance Of The Dssat Manihot-Cassava Model For Cassava Cultivation In The Recôncavo Baiano, Diego M. De Melo, Paola De F. Bongiovani, Fabio L.S. Costa, Patricia Moreno-Cadena, Alexandre B. Heinemann, Julian Ramirez-Villegas, Mauricio A. Coelho Filho

All Peer-Reviewed Publications

The aim of the present study was to calibrate the DSSAT MANIHOT-Cassava model with information from cassava varieties grown in the Recôncavo Baiano region, Bahia state, Brazil. The database used to calibrate the model was obtained in the dry sub-humid tropical climate in Cruz das Almas city, from 2019 to 2020. The model was calibrated with experimental data obtained under irrigated and rainfed conditions for the BRS Novo Horizonte and Eucalipto varieties. The calibration was carried out by adjusting parameters related to the characteristics of each variety. Model performance was evaluated with statistical indices that indicate the precision and accuracy …

Longitudinal And Ensemble Modeling Of Beef Cattle Feed And Water Intakes, Nathan El Blake

Graduate Theses, Dissertations, and Problem Reports (ETD)

Beef cattle production remains a cornerstone of global food systems, providing highly bioavailable protein and essential micronutrients that are difficult to secure from plant-based foods alone. Yet this production is also resource-intensive, requiring substantial land, feed, and water inputs while contributing significantly to greenhouse gas emissions. Efficiency of dry matter intake (DMI) and water intake (WI) is central to both productivity and sustainability, but accurate measurement of these traits—particularly in grazing systems—remains a major limitation. National WI standards continue to rely on pen-level data collected in the 1950s, while most existing DMI prediction equations perform poorly when applied beyond the …

Characterization Of Major Foliar Fungal Species Affecting Cucurbits In South Dakota, Janani Perera Waduwarage Dona

Electronic Theses and Dissertations

Cucurbit crops comprise the largest area in vegetable production in South Dakota (USDA 2022). Information on the prevalence, distribution, and fungicide sensitivity of their fungal pathogens are unknown. This study characterized the major foliar fungal species affecting cucurbits in South Dakota through a 2-year, state-wide survey. Between 2023 and 2024, 789 leaves were recovered from pumpkin, cucumber, watermelon, squash, and bottle gourd. Alternaria spp. (70.72% of leaves) Fusarium spp. (6.84%), Podosphaera xanthii (4.18%), both Alternaria spp. and Fusarium spp. (3.42%), and both Alternaria spp. and Podosphaera xanthii (1.90%), Stagonosporopsis spp. (1.27%) and other genera of fungi (4.94%) were identified using …

Epidemiological And Diagnostic Approaches For Soybean Cyst Nematode In South Dakota, Nabina Karki

Electronic Theses and Dissertations

Soybean cyst nematode (SCN), Heterodera glycines (HG) Ichinohe, is an endoparasitic nematode and one of the major yield-limiting pathogens of soybean (Glycine max L.) in the United States. Soybean cyst nematode alone accounts for more than $1.5 billion economic loss annually in North America. First reported in the U.S.A. in 1954 in New Hanover County, North Carolina and later in 1995 in Union County, South Dakota. Prior to this study, SCN has spread in 34 counties in the state. As a soil pathogen, which can adapt to most soil conditions under soybean production and beside soybean, it is hosted on …

Cover Cropping Strategies For Improving Weed Suppression, Yashar Askarzadeh

Electronic Theses and Dissertations

Cover crops (CCs) play an essential role in sustainable agriculture by providing multiple ecosystem services. However, adoption remains low due to concerns about economic returns, management complexity, and potential yield reductions in cash crops. Applying CCs uniformly across fields without accounting for spatial variability can result in inconsistent outcomes. A precision cover cropping system (PCCS), which incorporates site-specific management zones (MZs), offers a more targeted approach to improving performance while minimizing costs and uncertainties. This study explores the interaction between CCs and field variability through complementary field and greenhouse experiments. The field experiment demonstrates that field heterogeneity significantly influences CC …

Isolation, Characterization & Identification Of Cultivable Field Pea Seed Bacteria In South Dakota, Diana Wairimu Njuguna

Electronic Theses and Dissertations

Pea (Pisum sativum L.) is a legume, cultivated on over 25 million acres, particularly in Canada, France, China, Russia, and the United States. Its seeds harbor microbiota including bacteria and fungi, either on the surface (epiphytes) or within seed tissues (endophytes). These microbes can be pathogenic or beneficial, enhancing seedling metabolism and protection from environmental stresses. Characterizing beneficial seed microbiota enables development of microbial inoculants for seed treatment. Seeds from 12 varieties (green or yellow seed coats) were harvested from Sturgis and Dakota Lakes in 2021. Epiphytes were extracted using sonication followed by grinding the seeds to obtain endophytes. Isolates …

Evaluating The Adaptation Of Taro (Colocasia Esculenta) To West Virginia Climatic Conditions, Kayode Joseph Ajayi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Climate change impacts agriculture and food security across the globe, therefore higher temperatures could increase in the length of the growing period and new crops would take advantages of. Research was conducted in Morgantown, WV in 2022 and 2023 to understand the growth pattern of Taro in West Virginia, and to analyzing the chemical composition of the Taro plant. The experiment was a completely randomized design in direct planting-low tunnel technology (2 replications, and 10- plants/plot), and two fertilization treatments (fertilized and non-fertilized). Spacing was 1 m within and between rows. Data were subjected to ANOVA using SAS. Dependent variables …

Biphasic Models Improved S-Metolachlor Dissipation Endpoint Predictions, K. Badou-Jeremie Kouame, Mary Savin, Cammy Willett, Thomas R. Butts, Erin Grantz, Matthew Bertucci, Samantha E. Robinson, Rodrigo Werle, Nilda Roma-Burgos

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Accurate predictions of herbicide dissipation endpoints are essential for making environmental management decisions, estimating the duration of weed control, and deciding crop replant and rotation options. The performance of the single first-order (SFO), first-order multiple-compartment (FOMC), bi-exponential (BEXP), first-order double-exponential decay (FODED), and first-order two-compartment (FOTC) was evaluated to describe S-metolachlor dissipation. Results showed that the BEXP and FOTC were not appropriate. The FODED was ranked as the top model with the lowest Akaike's information criterion (AICc) value among the other three candidate models and was followed by the FOMC model. The SFO displayed the largest root mean square …

Sensitivity Of Difficult-To-Control Palmer Amaranth Accessions To Fluridone And Diflufenican, Maria Carolina Souza, Matthew Coleman Woolard, Jason K. Norsworthy, Tristen H. Avent, Tristen H. Avent, Tom Barber, Rodrigo Botelho

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Palmer amaranth (Amaranthus palmeri S. Watson) has evolved resistance to herbicides targeting nine sites of action. Phytoene desaturase-inhibiting herbicides remain among the few sites of action that are still effective in controlling Palmer amaranth. Greenhouse experiments were conducted to evaluate the effectiveness of fluridone and diflufenican in controlling difficult-to-control Palmer amaranth accessions collected in Arkansas from 2016 to 2022, to quantify the response of three accessions that exhibited low sensitivity to both herbicides, and to evaluate the effectiveness of photosystem II inhibitors alone and with fluridone or diflufenican on three accessions. At 14 days after a preemergence application, Palmer …

Phosphorus Buffering Determines How Soil Properties And Rainfall Influence Wheat (Triticum Aestivum) Yield Response To Phosphorus Fertiliser, Craig Scanlan, Raj Malik, Gustavo Boitt, Mark Gherardi, James Easton, Zed Rengel

Grain and Other Field Crops Research Articles

Context

Current decision support systems (DSS) for phosphorus (P) fertiliser were developed using data from historical cropping systems. An understanding of how soil properties and rainfall influence wheat (Triticum aestivum) response to P fertiliser in current systems is required to optimise P management. Aims

The aims of this study were to: (1) assess the soil properties that have the greatest influence on relative yield; (2) examine how rainfall conditions influence relative yield; and (3) examine whether there were interactive effects between rainfall and soil properties on relative yield. Methods

Forty P rate-response field experiments were completed in Western …

Comparative Study Of Rice Morphological And Physiological Characteristics Of Rice Grown Under Organic And Inorganic Farming, Amad Safrudin, Ratna Dewi, Dulbari

Jurnal Kultivasi

Organic farming practices have shown a potential to improve rice yields, aside from the popular conventional ones. This study aimed to comparatively analyze the morpho-physiological characteristics of rice plants grown under organic and inorganic farming. This research was conducted at the Polinela Organic Farm experimental station (5°21'10"S 105°13'43"E, 114 m sea above level), from February to April 2023 using a completely randomized design. The results showed that rice grown organically exhibited a notably higher chlorophyll index and actual water use efficiency compared to those grown inorganically. Conversely, inorganic farming resulted in a greater number of tillers than organic farming. However, …

Maize Hybrids’ Genetic Variability Based On Qualitative And Quantitative Traits, Slamet Bambang Priyanto, Herawati, Suwarti, Ayyub Ar Rahman, Nining Nurini Andayani, Abdul Fattah, Muhammad Azrai

Jurnal Kultivasi

Genetic variability was a prerequisite to doing a plant breeding program. A broad genetic variability allows plant breeders to select a desired genotype. This research aims to assess the maize hybrid's genetic variability based on qualitative and quantitative traits. This research was conducted in the Bone district, south Sulawesi, from November 2022 to March 2023. Fifteen maize hybrids were arranged in a randomized complete block design with three replications. The variables observed are qualitative and quantitative traits. Principal component (PCA) and cluster analyses assessed the genetic variability. The result indicated that based on a loading factor greater than 0.70, the …

Evaluation Of Biochar As A Remediation Tool For Aminopyralid Contaminated Compost, Steven James Parris

Masters Theses & Specialist Projects

Aminopyralid is a synthetic auxin herbicide which is applied to grass pastures to control broadleaf weed populations. Aminopyralid can contaminate compost through inputs derived from treated pastures such as manure and grass clippings. This possibility poses the threat of inadvertent herbicide exposure to sensitive vegetable plants through using compost contaminated with aminopyralid. Biochar can absorb pollutants and has a synergistic effect with compost when applied to the compost mixture. This study examined the relationship between biochar and aminopyralid through compost consisting of dairy manure and sawdust 1:1 mixture, aminopyralid (10μg/kg), and biochar at four treatment levels of total mass of …

Assessment Of Drought Tolerance In Mung Bean [Vigna Radiata (L.) Wilczek] Through Phenology, Growth, Protein Yield, And Cluster Heatmap Analysis, Rafiqul Islam, Jamil Hossain, Shamsul Huda, Mohammad Golam Azam, Faruk Hossain, Aktar Uz Zaman, Safiqul Moula, Nasir Uddin Ahmed, Jamal Hossain, Ayman El Sabagh, Mohammad Sohidul Islum

The Philippine Agricultural Scientist

Mung bean [Vigna radiata (L.) Wilczek] cultivation is challenging under the changing climate as less precipitation during the summer season, which is becoming increasingly common, results in soil moisture deficiency and affects production especially at the early growth stages. Hence, this study was conducted to assess the phenology, growth, and protein yield traits of mung bean related to drought tolerance. Eight mung bean genotypes were grown in pots inside a rain-out shelter under well-watered (WW) and water-deficit (WD) conditions. These genotypes included four water stress-tolerant genotypes: G-1 (BARI Mung-8), G-2 (BMX-010015), G-3 (BMX-08010-2), and G-4 (BMX-08009-7), as well as four …

Soybean Seed Yield Distribution Within The Canopy As Affected By Nitrogen Supply, Lucia Bonfanti

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Soybean [Glycine max (L.) Merr.] seed yield is influenced by the seasonal availability of resources (i.e., nutrients, light, and water). While nitrogen (N) supply is becoming a soybean yield-limiting factor, the N-induced effect in seed yield components is still unclear. The objective of this research was to assess the effect of N supply on soybean yield components distribution within the canopy. A Full-N treatment, which provided the crop with ample N supply, was compared against a Zero-N treatment in which the crop relied on soil N and biological N fixation at nine high-yielding irrigated soybean environments in Nebraska, with …

Interpreting The Spatial Distribution Of Soil Properties With A Physically-Based Distributed Hydrological Model, Zamir Libohova, Marcelo Mancini, Hans Edwin Winzeler, Quentin D. Read, Ning Sun, Dylan Beaudette, Candiss Williams, Joshua Michael Blackstock, Sergio H.G. Silva, Nilton Curi, Kabindra Adhikari, Amanda Ashworth, Joshua O. Minai, Phillip R. Owens

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Digital soil maps are commonly data-driven as the development of physically-based models for soil mapping is difficult due to the complexity of soils. However, physically-based hydrologic models have been successful in simulating water dynamics. Since water movement is a major driver of pedogenesis, the physical rules that govern water movement might help explain and predict the spatial variation of soil properties. Here, we demonstrate the novel use of a physically-based, distributed hydrologic model to inform the spatial distribution of soil properties. The Distributed Hydrology Soil Vegetation Model (DHSVM) was utilized to simulate soil moisture content (SM) and water table …

Compact Solar-Powered Plasma Water Generator: Enhanced Germination Of Aged Seed With The Corona Dielectric Barrier Discharger, Yiting Xiao, Yang Tian, Haizheng Xiong, Ainong Shi, Jun Zhu

Biological and Agricultural Engineering Faculty Publications and Presentations

Seed aging adversely affects agricultural productivity by reducing germination rates and seedling vigor, leading to significant costs for seed banks and companies due to the need for frequent seed renewals. This study demonstrated the use of plasma-activated water (PAW), generated by a solar-powered corona dielectric barrier discharger, to enhance germination rates of spinach seeds that had been stored at 4 °C for 23 years. Treating seeds with PAW at 17 kV for 15 min improved germination (by 135%) and seedling growth compared to untreated seeds. Through detailed analysis, beneficial PAW properties for seed development were identified, and a molecular mechanism …

Evaluating The Duckweeds Lemna Minor And Spirodela Polyrhiza As Alternative Aquatic Hosts For The Spread Of The Bacterial Wilt Pathogen, Ralstonia Solanacearum, Irelynn Smith

Honors Theses

Ralstonia solanacearum is a plant pathogen that causes bacterial wilt disease in major crops such as tomatoes and potatoes. Recently, this bacterium was discovered in floating pennywort (Hydrocotyle ranunculoides) and Pennsylvania smartweed (Polygonum pennysylvanicum), two previously unsuspected aquatic plants. Duckweed is an aquatic plant with a high level of resilience and short doubling time. Common duckweed (Lemna minor) has previously demonstrated its capability as a versatile high-yield infection model for other types of pathogenic bacteria. Given this newfound branch of aquatic hosts and the fact that duckweed is a common pond weed previously identified in several ponds located nearby infected …

Field Assessment Of Fertilization, Nursery, And Crop Management Practices Among Tomato (Solanum Lycopersicum L.) Growers In The Ilocos Provinces, Philippines, Annalissa Aquino, Sancho Bon, Angelica Guanlao, Ann Mylalulex Magnaye, Filomena Sta Cruz, Pompe C. Sta. Cruz

The Philippine Agricultural Scientist

Growth and yield of many economically important vegetables like tomatoes are heavily influenced by crop management practices, particularly fertilizer application, irrigation scheme, and pest management. To attain maximum tomato yields and increase farmers’ profits, these crop production components must be optimized in local farm levels. Before optimization measures can be conducted, baseline information on prevailing practices needs to be evaluated. To assess the nutrient management and other crop production practices of tomato farmers in the Ilocos provinces, Philippines, on-farm surveys were conducted in 16 and 18 barangays planting fresh-type and processing-type tomatoes, respectively. The study involved a total of 88 …

Nitrogen Limitation In Soybean: Physiology And Diagnosis, Luzviminda Ann Ramos Sazon

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In high-yield soybean environments, the seed yield is limited by nitrogen (N) supply. However, the response of soybean to N fertilizer application is inconsistent. Understanding the seasonal N uptake dynamics in soybean can provide insights on diagnosing N limitation if soybean. To understand soybean N dynamics, we assessed seasonal trends on dry matter and N accumulation in vegetative organs (leaves, stems, and petioles) from 42 field experiments. Each experiment included a ‘zero-N’ treatment, where crops relied on N supply from soil and biological N fixation (BNF), and a ‘full-N’ that received ample N via N fertilizer addition. Vegetative storage proteins …

Rice Response To Struvite And Other Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye, Diego Della Lunga, Kristofor R. Brye

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH₄PO₄⋅6H₂O), may provide a sustainable alternative to decreasing rock-phosphate reserves. Struvite can be generated via precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice (Oryza sativa) cultivar grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)]. Rice was …

Site Position, Tillage, And Soil Depth Effects On Soil Properties In A Furrow-Irrigated Rice Field On A Silt-Loam Soil, Hannah Nobles, Kristofor Brye, Diego Della Lunga

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The fundamental agronomic shift from conventional agricultural methods to conservation agriculture relies on understanding soil nutrient stratification with depth and under different tillage treatments. Assessment of nutrient stratification in the dynamic conditions of furrow-irrigated rice (Oryza sativa) systems in eastern Arkansas is absent. The objective of this study was to evaluate the effects of tillage [i.e., conventional tillage (CT) and no tillage (NT], site position (i.e., up-, mid-, and down-slope), soil depth interval (i.e., 0-10 and 10-20 cm), and their interaction on the difference (i.e., end of the season minus beginning of the season) in select soil chemical …

Enhancing Selection Intensity With High-Throughput Phenotyping Data In Plant Breeding, Ashmita Upadhyay

Graduate Theses and Dissertations

Genomic prediction (GP) has proven to be an essential tool to accelerate the cultivar development pipeline by predicting the performance of un-phenotyped lines in the field of plant breeding. However, the prediction accuracy is bounded by the heritability of the target trait, limiting the efficiency of the single-trait GP model. To overcome the limitation, a multi-trait genomic prediction model using high-throughput phenotyping (HTP) data can be used to leverage secondary traits to boost the predictive ability of the target trait. This study aimed to assess the efficiency of the multi-trait (MT)- GP model powered by HTP derived secondary traits in …

Association Mapping For Water Use Efficiency In Soybean Identifies Previously Reported And Novel Loci And Permits Genomic Prediction, Siva K. Chamarthi, Larry C. Purcell, Felix B. Fritschi, Jeffrey D. Ray, James R. Smith, Avjinder S. Kaler, C. Andy King, Jason D. Gillman

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Soybean is a major legume crop cultivated globally due to the high quality and quantity of its seed protein and oil. However, drought stress is the most significant factor that decreases soybean yield, and more than 90% of US soybean acreage is dependent on rainfall. Water use efficiency (WUE) is positively correlated with the carbon isotopic ratio ¹³C/¹²C (C13 ratio) and selecting soybean varieties for high C13 ratio may enhance WUE and help improve tolerance to drought. Our study objective was to identify genetic loci associated with C13 ratio using a diverse set of 205 soybean maturity …

Broad-Spectrum Resistance To Fungal Foliar Diseases In Wheat: Recent Efforts And Achievements, Amira M.I. Mourad, Asmaa A.M. Ahmed, P. Stephen Baenziger, Andreas Börner, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Wheat (Triticum spp.) is one of the most important cereal crops in the world. Several diseases affect wheat production and can cause 20-80% yield loss annually. Out of these diseases, stripe rust, also known as yellow rust (Puccinia striiformis f. sp. tritici), stem rust (Puccinia graminis f. sp. tritici), leaf rust (Puccinia recondita), and powdery mildew (Blumeria graminis f. sp. tritici) are the most important fungal diseases that infect the foliar part of the plant. Many efforts were made to improve wheat resistance to these diseases. Due to the continuous advancement in …

Disentangling Genotype And Environment Specific Latent Features For Improved Trait Prediction Using A Compositional Autoencoder, Anirudha Powadi, Talukder Zaki Jubery, Michael C. Tross, James C. Schnable, Baskar Ganapathysubramanian

Department of Agronomy and Horticulture: Faculty Publications

In plant breeding and genetics, predictive models traditionally rely on compact representations of high-dimensional data, often using methods like Principal Component Analysis (PCA) and, more recently, Autoencoders (AE). However, these methods do not separate genotype-specific and environment-specific features, limiting their ability to accurately predict traits influenced by both genetic and environmental factors. We hypothesize that disentangling these representations into genotype-specific and environment-specific components can enhance predictive models. To test this, we developed a compositional autoencoder (CAE) that decomposes high-dimensional data into distinct genotype-specific and environment-specific latent features. Our CAE framework employed a hierarchical architecture within an autoencoder to effectively separate …